Machine Type Communication (MTC) is also called Machine To Machine (M2M) communication between User Equipment (UE) or terminals, and is a main application form of the present Internet of things. Low power consumption and low cost are important guarantees for its large-scale application. So far, an M2M technology has gained support from multiple international renowned manufacturers and approval of mobile service providers of each country. At present, M2M equipment deployed on the market is mainly based on a Global System of Mobile communication (GSM). In recent years, more and more mobile service providers select Long Term Evolution (LTE) as a direction of evolution of a broadband wireless communication system in the future because LTE has higher spectral efficiency. Various kinds of LTE-based M2M data services will be more attractive.
SI of an existing LTE system includes: a Master Information Block (MIB) and System Information Block 1 (SIB1) to SIB16, wherein the MIB includes a limited number of parameters which are most essential and are sent most frequently; and SIB1 includes information about whether a terminal is allowed to access a cell or not, scheduling information of other SI, and the like. In the existing LTE system, other SIBs (i.e. SIB2 to SIB16) except SIB1 are mapped to different SI messages, wherein one SI message may bear only one SIB or bear multiple different SIBs with the same sending period. In addition, SIB1 and all of the SI messages are transmitted on a Physical Downlink Shared Channel (PDSCH), and are dynamically scheduled according to a Physical Downlink Control Channel (PDCCH) which bears downlink allocation information. Here, a scheduling period of SIB1 is fixedly 80 ms, the same content is retransmitted every 20 ms in the period, and transmission of SIB1 is fixedly implemented through the sub-frame 5 of even radio frames; and first transmission is started from a radio frame of which System Frame Number (SFN) mod 8 is 0 (mod represents remainder calculation). All the SI messages are dynamically scheduled within periodic time windows, each SI message is associated with one SI time window, and the SI time windows of different SI messages are not overlapped; and in addition, sizes of the SI time windows of all the SI messages are the same, and may be flexibly configured through SIB1. In the determined time windows, the corresponding SI messages are allowed to be scheduled within any sub-frame (except a Multicast Broadcast Single Frequency Network (MBSFN) sub-frame, a Time Division Duplex (TDD) uplink sub-frame and the sending sub-frames of SIB1).
Some MTC terminals are installed in basements of houses or positions covered by aluminium alloy windows or conventional thick-walled building structures. Compared with normal LTE terminals, these terminals may have extraordinarily high penetration loss at radio frequency interfaces, so that it is needed to enhance coverage of the MTC terminals. Here, a channel type to be enhanced includes: a Physical Uplink Shared Channel (PUSCH), a PDCCH, a Physical Uplink Control Channel (PUCCH) and the like. Coverage enhancement of a PDSCH includes coverage enhancement of broadcast SI and coverage enhancement of unicast data. In order to accumulate more energy to improve coverage, a repetition method is usually used for transmission enhancement of various types of channels.
If an SI transmission mechanism of the existing LTE system is applied to an MTC terminal in a coverage enhancement mode, the following problems may be caused: first, repetition of a PDCCH related to dynamic scheduling of SI may cause higher control overhead and longer time delay of access; and second, there are many types of SI at present and the transmission mechanism is complex, so that low cost and low complexity of the MTC terminal may not be achieved well.